Paul George top-scored with 28 points in Indiana's win over Miami in game six of the NBA Eastern Conference finals.

Getty Images: Ronald Martinez

The Indiana Pacers beat the Miami Heat 91-77 on Sunday (AEST) to force a decisive game seven in the National Basketball Association's Eastern Conference finals.

The deciding encounter in an enthralling series will be held in Miami on Tuesday (AEST) with the winner joining the San Antonio Spurs in the NBA finals, starting on Friday (AEST).

Leading 3-2, the Heat knew a win would secure their place in the finals for the third straight year but, with Dwyane Wade and Chris Bosh badly off-form and Chris Andersen suspended, Indiana took full advantage.

Paul George top scored with 28 points while Roy Hibbert was also outstanding for Indiana, providing a strong physical presence on defence, claiming 11 total rebounds and putting up 24 points.

"We didn't play our best basketball tonight and we were able to win. But we are going to have to play our best basketball to win down there in game seven," Indiana head coach Frank Vogel said.

LeBron James led the Heat with 29 points and Miami led 40-39 at half-time but was possibly fortunate to be in that position.

But in a dramatic reversal of game five's third quarter, when the defending NBA champions ran away with it, Miami fell to pieces this time, allowing Indiana to take a 17 point lead at one stage.

Miami reduced the deficit to four points in the last quarter after two 3-pointers from Mike Miller but the Pacers quickly regained control to set up a winner-takes-all game seven.

"Our team did a tremendous job and we have got just one more game to win - we are taking it back to South Beach," Hibbert said.

Bosh managed just 1-of-8 shooting from the field (5 points) with Wade only 3-of-11 (10) and their combined 15 points was their lowest haul as a pair in three seasons together.

Wade has been carrying a knee injury and when asked about how much of a factor that was in his performance, he said: "I don't want to talk about (it). I have been talking about it for two months, I've got nothing else to say".

Miami head coach Erik Spoelstra said he shouldered the responsibility for the poor return from the other two members of the 'Big Three'.

"They are obviously a major part of what we do and I have to find a way to get them into positions where they can be really aggressive," Spoelstra said.

"All of us were very disappointed about this game and letting this opportunity slip through our hands but you have to move on immediately.

"Game sevens are a treasure in pro sports, obviously we would like to have closed it out earlier but game sevens are the ones you will remember in 20 years' time."